Hydrangea macrophylla 'Bailmer' (PP 15,298) ENDLESS SUMMER® HYDRANGEA

3-5 ft. (Zone 4)  This one breaks the rules!  Normally the Hortensia varieties of Hydrangea bloom on two year old wood only, but this  Hydrangea blooms on both old and new wood.  Flower color varies by variety and by soil ph. (See general description for Hortensia type).
 
General Hydrangea Hortensia flower type

Hydrangeas with hortensia or mophead type flowers have sterile petals in large globose corymbs.  Flower color varies by variety and by soil ph.  Acidic ph for blue color, alkaline ph for pink.  Plant in part-shade to part-sun in well-drained organic soil.  Bloom in summer.